pgsql: Update timezone to C99

Update timezone to C99

This reverts changes done in PostgreSQL over the upstream code to
avoid relying on C99 <stdint.h> and <inttypes.h>.

In passing, there were a few other minor and cosmetic changes that I
left in to improve alignment with upstream, including some C11 feature
use (_Noreturn).

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/9ad2749f-77ab-4ecb-a321-1ca915480b05%40eisentraut.org

Branch
------
master

Details
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https://git.postgresql.org/pg/commitdiff/e6be84356bbbaf9f88b6a738e690d6fdff6fe483

Modified Files
--------------
src/timezone/README              |  14 ----
src/timezone/localtime.c         | 113 ++++++++++++++++----------------
src/timezone/pgtz.h              |   4 +-
src/timezone/private.h           |  28 ++++----
src/timezone/zic.c               | 135 ++++++++++++++++++---------------------
src/tools/pgindent/typedefs.list |   3 +
6 files changed, 136 insertions(+), 161 deletions(-)